Patent GB-904308-A (GB)
Title: Improvements in and relating to lapping or testing machines for gear wheels
IPC: F16H57/02
Filed: 1960-09-05
Abstract: 904,308. Gear-testing apparatus. VERWALTUNGSGESELLSCHAFT DER WERKZEUGMASCHINENFABRIK OERLIKON. Sept. 5, 1960 [Sept. 11, 1959], No. 30496/60. Class 106 (2). [Also in Group XXIII] In a machine for testing pairs of bevel gears the spindle 30 of one gear is mounted on a headstock 15 movable, against spring bias, towards the other gear, the headstock being secured by a clamping device 40 to a slidable platform 31, Fig. 3, after meshing the gears without back-lash, and the platform is moved back, with the headstock, through the required amount of back-lash or tooth clearance. The platform 31 is hydraulically -operated by a " drive " unit 60, Fig. 3, and the headstock 15 is movable hydraulically against a biasing spring 83 by a piston 84 and cylinder 85, the latter being secured to the platform 31, to form a setting-up unit. The drive unit 60 is operated by a valve controlling the ports 73, 72 having at one end a sensing feeler 66 and at the other end an extension of the stem 69 through a solenoid V3 which when energized moves the valve to the admission position in opposition to a spring 68. The flat head of the feeler 66 is engageable by cams 126 and 110 carried by slides 125 and 109, Fig. 5, respectively, the cams being so arranged that the first cam, 126, may slide past the second, 110, thereby taking over control of the valve from the first cam. The cam-carrying slides 125, 109, may be so relatively positioned by screwed spindles 124 and 108 respectively that this transference of contact with the feeler 66 is effected soon after the headstock 15 moves relative to the platform 31. The spindle 124 is driven, through gearing 123, by a reversible motor M3 controlled by switches E3, E4, mounted at the stroke limits of the slide 125 on a manuallyadjustable slide 117. The spindle 108 is manually rotatable, through gearing, by a shaft 102 having a cable-operated drum 103 rotatable by an axially movable and rotatable shaft 91 and cable-drum 93, against the biasing of a spiral spring 104 on the end of the shaft 102, the axial movement of the shaft 91 being effected by a solenoid MG against the opposition of a spring 96. Setting up is carried out initially without the gears to be tested. Referring to Figs. 6 and 7, the solenoid DV2 is first energized to push the main hydraulic system control valve 135 upwards, admitting pressure from the pump 132 to the clamping device 40 to release a spring-held clamp so that the headstock 15 is movable relative to the platform 31. Pressure is also admitted to the setting up cylinder 85 to displace the headstock by about half its possible movement. The solenoid V3 is then energized to push the control valve and feeler 66 to the right, Fig. 3, or in the meshing direction, followed by the drive cylinder 64 with the platform 31. Simultaneously, the motor M3 is started, moving the cam-carrying slide 125 to the switch E4 past the cam 110. The scale 23 is then rotated to move the slide 109 back to provide the required tooth clearance, the feeler 66 then contacting the cam 110 so that the clearance is transmitted by the drive or followup unit 60 to the platform 31. The gears 26, 27, Fig. 2, to be tested are then secured to their spindles by clamps 17, 18, and are movable manually by adjusting spindles 19, 20, 21, to bring them into the testing position. The pump motor M2 is then switched-off and the solenoid V3 is de-energized and the headstock 15 returns to its noback-lash position under the influence of the spring 83. The operational cycle is effected by closing switches H and S, starting the hydraulic pump motor M3 and moving the valve 135 downward by the solenoid DV1 and opening switches E6, E7, as the clamp 40 is moved to free the headstock 15 from the slide 31, the spring 68 retaining the valve 66 with its stem 69 bearing on the casing 11 in the neutral position with the platform 31 retracted. When the solenoid V3 is energized the platform moves towards the meshing position until the feeler 66 contacts the cam 126. A push-button switch S4 is then closed to start the motor M3 to move the slide 125. When the teeth of the gears are brought into mesh the headstock continues its movement until meshing without back-lash is effected, bringing the headstock to rest, but the platform 31 continues its movement (to the right of Fig. 3). Meanwhile the cam 126 has run past the cam 110 so that the latter takes over control of the drive unit control valve. The slide 125 continues until the cam 127 closes the switch E4 to operate relays controlling the motor M3 which is then stopped. When the push-button S4 is released the control valve 135 is moved by solenoid DV2 to the hydraulic release position of the clamping unit 40 so that the headstock 15 and slide 31 are held together by spring pressure, and switches E6 and E7 are closed. The running clearance of the gears is then effected by turning the shaft 91 clockwise to move back the slide 109, in accordance with the clearance indicated on the scale 23, and the setting is locked by serrations 94 engaging a plate 95, Fig. 5 shows the clearance adjusting shaft 91 in its free position with a zero-locating device 97 engaged.